The 60-year-old was ordered by doctors to remain immobile in a hospital bed with fractured vertebrae and a broken rib after falling from a hoist raising him to the stage at a rally just days before the May 11 general election.
Shireen Mazari, spokeswoman for Khan's Pakistan Tehreek-e-Insaaf (PTI) party, said the former cricket star was feeling better and had managed to walk in hospital.
"Imran Khan will be discharged from hospital Wednesday," Mazari told AFP. "I have just talked to Imran Khan who told me that he will be going home tomorrow."
Khwaja Nazir, spokesman for Lahore's Shaukat Khanum Memorial Hospital, where Khan has been treated, confirmed that the PTI chief would be moving home on Wednesday.
Mr Khan electrified much of the campaign with his calls for reform and galvanised many young people to take part for the first time.
The election was won by the Pakistan Muslim League (N) of former prime minister Nawaz Sharif, but the PTI scored a major breakthrough, finishing in third place with 28 national assembly seats, according to partial results.